Re: [Bug-apl] Modulo or residue function is not generating consistent complete residue systems for some arguments

[Elias Mårtenson]

You are right of course. I forgot about that part.

Speaking of which, I have often wished that - and ÷ behaved the same. I'm really glad that ⍨ exists.

On 20 June 2017 at 16:15, Jay Foad <address@hidden> wrote:

You need to swap the arguments; "⍺|⍵" in APL is "⍵ mod ⍺" or "⍵ rem ⍺" or "⍵ % ⍺" in most other systems.

On 20 June 2017 at 09:11, Elias Mårtenson <address@hidden> wrote:

Wolfram Alpha tells me it should be 5J3:

https://www.wolframalpha.com/input/?i=(5%2B3i)+mod+(14%2B5i)

Regards,

Elias

On 20 June 2017 at 16:02, Jay Foad <address@hidden> wrote:

With the demo version of APL2 I get:

      5J3 ∣ 14J5

¯4J1

      5J3 | 1J4

¯4J1

      5J3 | ¯4J1

¯4J1

Jay.

On 19 June 2017 at 18:03, Frederick Pitts <address@hidden> wrote:

Jürgen,

        With gnu apl (svn 961 on Fedora 25, Intel(R) Core(TM) i7-6700
CPU), the residue function (∣) yields the following:

      5J3 ∣ 14J5
1J4
      5J3 | 1J4
¯4J1
      5J3 | ¯4J1
¯4J1
The above result means that two elements in the complete residue system
(CSR) for mod 5J3 are equal, i.e. 1J4 = ¯4J1 mod 5J3, which is not
allowed.  None of the elements of a CSR can be equal modulo the CSR's
basis.

Regards,

Fred